Method of thin film deposition in trenches

ABSTRACT

Embodiments of the present disclosure generally relate to processing a workpiece containing a substrate during deposition, etching, and/or curing processes with a mask to have localized deposition on the workpiece. A mask is placed on a first layer of a workpiece, which protects a plurality of trenches from deposition of a second layer. In some embodiments, the mask is placed before deposition of the second layer. In other embodiments, the second layer is cured before the mask is deposited. In other embodiments, the second layer is etched after the mask is deposited. Methods disclosed herein allow the deposition of a second layer in some of the trenches present in the workpiece, while at least partially preventing deposition of the second layer in other trenches present in the workpiece.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit to U.S. Appl. No. 62/865,001, filed onJun. 21, 2019, and U.S. Appl. No. 62/834,832, filed on Apr. 16, 2019,which are herein incorporated by reference in their entirety.

BACKGROUND Field

Embodiments of the present disclosure generally relate to a method, and,more specifically, to a method of thin film deposition in trenches.

Description of the Related Art

In optical devices, such as virtual or augmented reality sets, awaveguide combiner is often used to couple a virtual image, transportlight inside a glass substrate through total internal reflection, andthen couple the image when reaching the position of viewer's eye. Forlight coupling and decoupling, slanted features and trenches in thewaveguide combiner are usually applied as gratings for lightdiffraction. The orientation of lines (fins) controls the lightpropagation direction, whereas the tilted angle controls the efficiencyof desired order(s) of diffraction.

Selective deposition in trenches has important industrial applicationsfor optical devices. Precise control of the material properties of thedeposited films, such as the refractive index, is necessary to ensureproper functioning of these devices. In addition, film growth withoutunwanted voids or holes is needed to ensure proper diffraction,reflection, and refraction of incident light on the optical structures.Thus, even film growth is required, along with selectivity, to ensurethat the correct portions of the structures receive the films withdesired material properties.

Traditional selective deposition processes often include chemicalmechanical polishing (CMP) techniques to remove excess film growth andensure that film growth occurs only in desired portions of theworkpiece. However, CMP techniques are unable to remove film growth intrenches, as CMP techniques are surface level techniques. Also, theharsh mechanical condition during CMP can damage the underlyingstructures on the workpiece.

Therefore, improved methods for selectively depositing layers on aworkpiece with trenches are needed.

SUMMARY

In one or more embodiments, a method for processing a workpiece isprovided, including applying a mask on a first layer disposed on asubstrate, wherein the mask covers a first portion of the first layerand leaves exposed a second portion of the first layer, depositing asecond layer on the second portion of the first layer, removing the maskfrom the first portion of the first layer, wherein the first portion ofthe first layer is exposed and the second portion of the first layercontains the second layer deposited thereon, and exposing the secondlayer to a curing process.

In other embodiments, a method for processing a workpiece is provided,including depositing a second layer including an uncured composition ona first layer disposed on a substrate, applying a mask on the secondlayer, wherein the mask covers a first portion of the second layer andleaves exposed a second portion of the second layer, exposing the maskand the second portion of the second layer to a curing process, whereinthe mask shields the first portion of the second layer from the curingprocess while the second portion of the second layer is at leastpartially cured during the curing process, and wherein subsequent to thecuring process, the first portion of the second layer includes theuncured composition and the second portion of the second layer includesa cured composition formed from the uncured composition, and removingthe mask and the first portion of the second layer including the uncuredcomposition.

In other embodiments, a method for processing a workpiece is provided,including depositing a second layer including an uncured composition ona first layer disposed on a substrate, applying a mask on the secondlayer, wherein the mask covers a first portion of the second layer andleaves exposed a second portion of the second layer, exposing the maskand the second portion of the second layer to an etching process,wherein the mask shields the first portion of the second layer from theetching process while the second portion of the second layer is at leastpartially etched during the etching process, and removing the mask.

The methods disclosed allow for selective deposition in trenches withoutrequiring a CMP process. The selective deposition described hereinallows for deposition in some trenches, and prevents deposition in othertrenches.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentdisclosure can be understood in detail, a more particular description ofthe disclosure, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlyexemplary embodiments and are therefore not to be considered limiting ofits scope, may admit to other equally effective embodiments.

FIGS. 1A-1E illustrate schematic views of a workpiece being processed atdifferent intervals during a process that includes depositing with amask, according to one or more embodiments described and discussedherein.

FIG. 2 is a flow diagram of method operations for depositing a secondlayer on a workpiece using a mask, according to one or more embodimentsdescribed and discussed herein.

FIGS. 3A-3E illustrate schematic views of a workpiece being processed atdifferent intervals during a process that includes curing with a mask,according to one or more embodiments described and discussed herein.

FIG. 4 is a flow diagram of method operations for depositing a secondlayer on a workpiece using a curing process and a mask, according to oneor more embodiments described and discussed herein.

FIGS. 5A-5F illustrate schematic views of a workpiece being processed atdifferent intervals during a process that includes etching with a mask,according to one or more embodiments described and discussed herein.

FIG. 6 is a flow diagram of method operations for depositing a secondlayer on a workpiece using a mask and an etching process, according toone or more embodiments described and discussed herein.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe Figures. It is contemplated that elements and features of one ormore embodiments may be beneficially incorporated in other embodiments.

DETAILED DESCRIPTION

Embodiments of the present disclosure generally relate to processing aworkpiece containing a plurality of features and trenches. A combinationof masks, curing, and etches allows for selective deposition on variousportions of the workpiece. Films are selectively deposited on onlycertain parts of a workpiece, filling some trenches, and not fillingothers. The embodiments disclosed herein are especially useful for, butnot limited to, selectively depositing film material in certaintrenches, while preventing deposition in other trenches.

As used herein, the term “about” refers to a +/−10% variation from thenominal value. It is to be understood that such a variation can beincluded in any value provided herein.

Mask Deposition Followed by Second Layer Deposition

FIG. 1A depicts a workpiece 100 which includes a first layer 110disposed on a substrate 102. The first layer 110 can includemonocrystalline silicon (Si), polysilicon, amorphous silicon, siliconnitride (SiN), silicon oxide (SiO), silicon oxynitride (SiON), fusedsilica, one or more metal oxides, doped derivatives thereof, or anycombination thereof. The first layer 110 can include a plurality ofstructures 114, 115 formed therein. The plurality of structures 114, 115can include vertical fins, slanted fins, or pillars (e.g., nanopillars).

A plurality of trenches 112, 113 are formed or otherwise defined withinthe first layer 110 and between the structures 114, 115. Trenches 112,113 include one or more passageways, vias, spaces, gaps, voids, or holesadjacent any of the structures 114, 115. The trenches 112, 113 can be atan angle θ to the surface of the first layer 110, such as from about 15°to about 75°. In some embodiments, the angle θ can be from about 15°,about 20°, about 25°, or about 30° to about 45°, about 55°, about 65°,or about 75°. Each trench 112, 113 can have the same or differentspacing between adjacent trenches. Each trench 112, 113 can have thesame or different widths of the other trenches. Each trench 112, 113 canhave the same or different depths of the other trenches. Each trench112, 113 can have the same or different angle θ of the other spaces.Trench 112, 113 depths can vary from about 100 nm to about 1 um, trenchwidths and trench to trench spacing are from about 50 nm to about 600nm.

The workpiece 100 has a second plurality of structures 114 and a secondplurality of trenches 112 disposed in the second portion 118 of thefirst layer 110, the structures separated by the trenches. The firstplurality of trenches 113 has at least one trench that makes an angle θof about 15° to about 75° with respect to the surface 110S of the firstlayer 110, according to one or more embodiments described and discussedherein. The second plurality of trenches 112 has at least one trenchthat makes an angle θ of about 15° to about 75° with respect to thesurface of the first layer 110, according to one or more embodimentsdescribed and discussed herein. The angles 8 of the first trench 113 andthe second trench 12 can be the same or different from one another.

In some embodiments, the first layer 110 is a surface of the substrate102, and the substrate 102 can include one or more structures 114, 115.The substrate 102 can include a wafer or panel substrate capable ofhaving material, layers, films, and/or the like deposited thereon. Thesubstrate 102 can include silicon (doped or undoped), crystallinesilicon, silicon oxide, doped or undoped polysilicon, or the like, agermanium (Ge) substrate, a silicon germanium (SiGe) substrate, a GroupIII-V compound substrate, such as a gallium arsenide (GaAs) substrate, asilicon carbide (SiC) substrate, a patterned or non-patternedsemiconductor-on-insulator (SOI) substrate, a carbon-doped oxide, asilicon nitride, a solar array, solar panel, a light emitting diode(LED) substrate, or any other materials such as metals, metal alloys,and other conductive materials. In some examples, the substrate 102 canbe disposed on a substrate holder or a substrate pedestal, a chuckingplate, or the like. The substrate 102 can include a plurality of layersor films, such as a semi-insulating material and a semiconductingmaterial, where the semi-insulating material has a higher resistivitythan the semiconducting material. The substrate 102 is not limited toany particular size or shape (e.g., round, rectangular, or square). Insome examples, the substrate 102 is round and has a diameter of about100 mm to about 450 mm.

FIG. 2 is a flow diagram of method operations 150 for depositing asecond layer 130 on the first layer 110 using a mask 120, according toone or more embodiments described and discussed herein. Although themethod 150 operations are described in conjunction with FIGS. 1A-1E and2 , persons skilled in the art will understand that any systemconfigured to perform the method operations, in any order, falls withinthe scope of the embodiments described herein.

The method 150 begins at operation 152, where a mask 120 is applied,placed, deposited, formed, or otherwise disposed on the first layer 110,as depicted in FIG. 1B. The mask 120 has a predetermined pattern thatcan be transposed to the underlying layer, such as the first layer 110.The mask 120 covers a first portion 116 of the first layer 110 andleaves exposed a second portion 118 of the first layer. The mask 120 canbe or include a contact mask, a proximity mask, a projection mask, ordicing tape. The mask 120 can be separate from the processing chamber,or inside the processing chamber as a movable part. In some examples,the mask 120 can be or include a photo mask in a UV cure process and canbe incorporated into a UV chamber or a photolithography tool.

The mask 120 has a thickness from about 10 μm to about 1 mm, such asfrom about 100 μm to about 500 μm. The thickness of the mask 120 can bedesigned to reduce the shadowing effect, which can produce non-uniformdeposition close to the edge of the mask. For example, the mask 120 hasa relatively small thickness, e.g., from about 100 μm to about 150 μm,to reduce the shadowing effect.

At operation 154 of the method 150, a second layer 130 is deposited onthe second portion 118 of the first layer 110, as well as the mask 120,as depicted in FIG. 1C. The second layer 130 is at least partiallydeposited within the second plurality of trenches 112. The mask 120covers and can substantially or completely protect or shield the firstportion 116 of the first layer 110 from the second layer 130 depositingon the first portion 116. In some examples, residual amounts of materialof the second layer 130 can eventually contaminate the first portion 116of the first layer 110. Also, depending on the composition of the secondlayer 130 and the specific deposition process used to deposit orotherwise form the second layer 130, the mask 120 can include a layer132 of the same material as the second layer 130 and/or can containvarious byproducts, particulates, and/or other contaminants thereon.

The second layer 130 is deposited by chemical vapor deposition (CVD),plasma-enhanced CVD (PE-CVD), sub-atmospheric CVD (SA-CVD), high densityplasma CVD (HDP-CVD), flowable CVD (FCVD® processes), atomic layerdeposition (ALD), furnace ALD, thermal ALD, plasma-enhanced ALD(PE-ALD), physical vapor deposition (PVD), ion beam deposition,spin-coating, or any combination thereof. The second layer 130 includesa coating material, such as spin-on-carbon, epoxy, naphthalene resin(C₁₀H₈), organic planarization layer (OPL), poly(methyl methacrylate)(PMMA), polysilazane, polysiloxane, photoresists, or electron-beam(e-beam) resists. The second layer 130 can also include silicon oxide(SiO), silicon oxynitride (SiON), silicon nitride (SiN), silicon carbide(SiC), silicon oxycarbide (SiOC), silicon hydroxynitride (SiOHN),amorphous silicon (α-Si), polysilicon, silicon-containinganti-reflective coating (SiARC), aluminum oxide (Al₂O₃), carbon (C),carbon hydroxide (COH), alloys thereof, doped derivatives thereof, orany combination thereof. In one or more examples, the second layer 130can have a refractive index (RI) of about 1.05 to about 4.50. Theoptical and gap fill properties of the second layer 130 can be tunedthrough polymer type and functional groups. For example, methyl (CH₃—)groups or cage-like hydrogen silsesquioxane (HSQ) groups are known toreduce the RI of the second layer 130.

A silicon precursor, such as trisilylamine (TSA) (N(SiH₃)₃), silanes,tetrasilane (Si₄H₁₀), tetraethyl orthosilicate (TEOS),tetramethoxysilane (TMOS), or octamethylcyclotetrasiloxane (OMCTS), canbe used to deposit silicon-containing second layers 130, such assilicon, silicon oxide, or silicon oxynitride, during a CVD process. Asilicon precursor, such as trisilylamine (TSA) and a nitrogen precursor,such as ammonia (NH₃), can be used to deposit a silicon oxynitride layerduring a CVD process. A silicon precursor, such as polysiloxane, can beused to deposit a silicon oxide layer during a spin-on process.

The deposition of the second layer 130 can be performed at a substratetemperature or a processing chamber temperature from about 23° C. toabout 400° C. For example, a CVD or ALD process can be performed at asubstrate temperature or a processing chamber temperature from about 23°C. to about 100° C. A spin coating process can be performed at asubstrate temperature or a processing chamber temperature at about 23°C. A wet etch can be performed after deposition of the second layer 130,in order to remove residual deposition of the second layer present underthe mask 120.

At operation 156 of the method 150, the mask 120 is removed from thefirst portion 116 of the first layer 110. Thereafter, the first portion116 of the first layer 110 is exposed or left bare and the secondportion 118 of the first layer 110 contains the second layer 130deposited thereon, as depicted in FIG. 1D. Various materials (e.g., thelayer 132), particulate, or other contaminant contained on the mask 120can be removed before removing the mask 120 and/or at the same time. Themask 120 and the first portion 116 of the second layer 130 are removedin the same processing step, according to one or more embodimentsdescribed and discussed herein. The mask 120 and the first portion 116of the second layer 130 are sequentially removed in different processingsteps, according to one or more embodiments described and discussedherein.

In one or more embodiments, the method 100 can include removing residualmaterial from the first portion 116 of the first layer 110 during anetching process subsequent to removing the mask 120. The etching processcan include a wet etch process and includes exposing the residualmaterial to a solution containing hydrofluoric acid (HF), phosphoricacid (H₃PO₄), one or more hydroxides (e.g., sodium hydroxide (NaOH),potassium hydroxide (KOH), lithium hydroxide (LiOH), ammonium hydroxide(NH₄OH)), or salts thereof. A dilute hydrofluoric acid (DHF) solutionhaving a concentration from about 50:1 to about 1,000:1 (in water) canbe used during an etching process, such as for a second layer 130including SiON. The etching process can be a dry etch process andincludes exposing the residual material to a plasma containing fluorine(F), chlorine (Cl), compounds thereof, ions thereof, or any combinationthereof, such as for a second layer 130 including SiON.

At operation 158 of the method 150, the second layer 130 is converted toa cured composition 131, as depicted in FIG. 1E. The curing processdrives out unwanted solvents from the second layer 130, solidifies andstabilizes the second layer, and can also modify chemical and opticalproperties of the second layer, converting the second later to the curedcomposition 131. The curing process or treatment can be or include athermal curing process, an ultraviolet (UV) curing process, aplasma-assisted treatment process, an ion beam treatment process, anelectron beam (e-beam) treatment, or any combination thereof, accordingto some embodiments.

The curing process can be performed at a temperature from about 23° C.to about 400° C. If UV light is applied, the UV wavelength can be abroadband wavelength from about 190 nm to about 500 nm, or singlewavelength excimer lasers with wavelengths of about 193 nm, 248 nm, or365 nm. The UV curing time can vary from about 1 minute to about 10minutes. The second layer 130 is exposed to ozone (O₃) during the curingprocess, according to one or more embodiments described and discussedherein. In some embodiments, the curing process can include exposing thesecond layer 130 to one or more processing gases or compounds during thetreatment or process, such as argon (Ar), helium (He), oxygen (O₂),ozone, hydrogen gas (H₂), nitrogen gas (N₂), ammonia, water, ethylene(C₂H₄), acetylene (C₂H₂), or any combination thereof. The curing processis used to modify the second layer 130 film composition and stress asrequired for a given application. Optical properties of the second layer130 can be tuned by material design (choice of polymer and functionalgroups, binder, and solvent), and baking condition (e.g., step-wisebaking) to control crosslinking, solvent evaporation, and formation ofnanoporosity. In addition, the cured composition 131 is easier or moredifficult to remove from the workpiece 100 than the unmodified secondlayer 130.

For example, a second layer 130 including FCVD-deposited SiONH can becured into a cured composition 131 including SiO. In an additionalexample, a second layer 130 including a spin coating-deposited polymerand solvent layer can be cured into a cured composition 131 includingCHO, wherein the cured composition includes a crosslinked polymer.

In one or more embodiments, the second layer 130 is deposited using FCVDusing TSA/NH₃/O₂ precursors at a temperature from about 23° C. to about100° C., the second layer is cured using a baking process attemperatures from about 23° C. to about 400° C. while ozone is applied,and a wet etch including DHF is applied.

In other embodiments, the second layer 130 is deposited using spincoating, the second layer includes an organic planarization layer (OPL)including a polymer including C and H, the second layer is cured using abaking process at temperatures from about 250° C. to about 400° C., anda wet etch including a sulfuric peroxide mix (SPM) is applied.

As described above, a mask is deposited on a first layer. A second layeris deposited on the workpiece, but the mask prevents deposition of thesecond layer in the first plurality of trenches disposed underneath themask. The mask is removed, and thus the second layer is grown such thatmaterial of the second layer is present in the second plurality oftrenches, but not the first plurality of trenches.

The mask protects the first plurality of trenches from being filled withthe second layer, while still allowing the second plurality of trenchesto be filled with the second layer. The method as described above workswell for films that do not require curing in order to be removed fromthe workpiece.

Second Layer Deposition Followed by Mask Deposition

FIG. 3A depicts a workpiece 200, which includes the first layer 110disposed on the substrate 102 and containing the plurality of trenches112, 113 and the one or more structures 114, 115 as previously discussedfor the workpiece 100 in FIG. 1A.

FIG. 4 is a flow diagram of method 250 operations for depositing asecond layer 230 on the workpiece 200, including curing and using a mask120, according to one or more embodiments described and discussedherein. Although the method 250 operations are described in conjunctionwith FIGS. 3A-3E and 4 , persons skilled in the art will understand thatany system configured to perform the method operations, in any order,falls within the scope of the embodiments described herein.

The method 250 begins at operation 252, where a second layer 230containing an uncured composition is deposited on the first layer 110,as depicted in FIG. 3B. The second layer 230 fills the first pluralityof trenches 113 and the second plurality of trenches 112. The secondlayer 230 also extends along and covers the first layer 110. The secondlayer 230 is deposited by any of the methods disclosed in the discussionof the deposition of second layer 130 FIG. 1B above. The materials ofthe second layer 230 is similar that of the second layer 130 describedabove. The deposition of the second layer 230 can be performed at asubstrate temperature or a processing chamber temperature similar tothat of second layer 130 described above.

At operation 254 of the method 250, the mask 120 is applied, placed,deposited, formed, or otherwise disposed on the second layer 230, asdepicted in FIG. 3C. The content of the mask 120 and the application ofthe mask is similar to that of operation 152 described above.

At operation 256 of the method 250, the workpiece 200, including themask 120 and a second portion 218 of the second layer 230, is exposed toa curing process, as depicted in FIG. 3D. The mask 120 shields orotherwise protects a first portion 216 of the second layer 230 from thecuring process while the second portion 218 of the second layer 230 isat least partially cured, substantially cured, or completely curedduring the curing process. Subsequent to the curing process, the firstportion 216 of the second layer 230 contains the uncured composition.The second portion 218 of the second layer 230 contains a curedcomposition 231 formed from the uncured composition during the curingprocess. The curing process is similar to that of the operation 158described above.

At operation 258 of the method 250, the mask 120 and the first portion216 of the second layer 230 containing the uncured composition areremoved from the workpiece 200, as depicted in FIG. 3E. The mask 120 canbe removed before removing the first portion 216 of the second layer230. The mask 120 and the first portion 216 of the second layer 230 canremoved during the same process. The first portion 216 of the layer canbe removed by an etching process. The etching process can include a wetetch process and includes exposing the uncured material to a solutioncontaining hydrofluoric acid, phosphoric acid, one or more hydroxides(e.g., sodium hydroxide, potassium hydroxide, lithium hydroxide,ammonium hydroxide), or salts thereof. In one or more examples, a DHFsolution having a concentration from about 50:1 to about 1,000:1 (inwater) is used during an etching process. The etching process caninclude a dry etch process and includes exposing the uncured material toplasma containing oxygen, fluorine, chlorine, compounds thereof, ionsthereof, or any combination thereof.

In other embodiments, the second layer 330 is deposited using FCVD usingTSA/NH₃/O₂ precursors at a temperature from about 23° C. to about 100°C., the second layer is cured using a baking process at temperaturesfrom about 0° C. to about 400° C. while ultraviolet (UV) light is at awavelength of about 193 nm to about 500 nm for about 1 minute to about10 minutes, and a dry or wet etch including DHF is applied.

In other embodiments, the second layer 330 is deposited using FCVD usingOMCTS/TMOS/O₂ precursors at a temperature from about 23° C. to about100° C., the second layer is cured using a baking process attemperatures from about 0° C. to about 400° C. while ultraviolet (UV)light is applied at a wavelength of about 193 nm to about 500 nm forabout 1 minute to about 10 minutes, and a dry etch including oxygenplasma is performed.

As described above, a second layer is deposited on the first layer,filling both the first plurality of trenches and the second plurality oftrenches. A mask is placed over the first portion of the second layer,and the mask protects the first layer from the curing process. Thecuring process converts the exposed second portion of the second layerinto a cured composition. When the mask is removed, the first portion ofthe second layer is removed along with the mask. The remaining curedcomposition fills the second plurality of trenches, but the firstplurality of trenches is empty.

The mask protects the first plurality of trenches from being cured withthe second layer, while still allowing the second plurality of trenchesto be filled with the cured second layer. The method as described aboveworks well for films that require curing after deposition.

Second Layer Deposition Followed by Etching Process

FIG. 5A depicts a workpiece 300, which includes a first layer 110disposed on the substrate 102 and containing the plurality of trenches112, 113 and the plurality of structures 114, 115 as previouslydiscussed for the workpiece 100 in FIG. 1A.

FIG. 6 is a flow diagram of method 350 operations for depositing asecond layer 330 on the workpiece 300, including using the mask 120 andan etching process, according to one or more embodiments described anddiscussed herein. Although the method 350 operations are described inconjunction with FIGS. 5A-5F and 6 , persons skilled in the art willunderstand that any system configured to perform the method operations,in any order, falls within the scope of the embodiments describedherein.

The method 350 begins at operation 352, where a second layer 330containing an uncured composition is deposited, formed, placed, orotherwise disposed on the first layer 110, as depicted in FIG. 5B. Thesecond layer 330 fills the first plurality of trenches 113 and thesecond plurality of trenches 112. The second layer 330 also extendsalong and covers the first layer 110. The second layer 330 is depositedby any of the methods disclosed in the discussion of FIG. 1B above. Thematerials of the second layer 330 is similar that of the second layer130 described above. The deposition of the second layer 330 can beperformed at a substrate temperature or a processing chamber temperaturesimilar to that of second layer 130 described above.

At optional operation 354 of the method 350, the second layer 330 isexposed to a curing process, converting the second layer to a modifiedsecond layer 331, as depicted in FIG. 5C. The curing process is similarto that described in operation 158 as described above. Although thefollowing operations refer to the modified second layer 331, it is to beunderstood that the same process can be applied to the second layer 330as deposited, without the curing process described above.

At operation 356 of the method 350, the mask 120 is applied, placed,deposited, formed, or otherwise disposed on the second layer 330, asdepicted in FIG. 5D. The deposition of the mask 120 is similar to thatdescribed in operation 152 as described above.

At operation 358 of the method 350, the workpiece 300, including themask 120 and a second portion 318 of the modified second layer 331, isexposed to an etching process, as depicted in FIG. 5E. The mask 120shields or otherwise protects a first portion 316 of the second layer330 from the etching process, while the second portion 318 of themodified second layer 331 is at least partially etched away. Subsequentto the etching process, the first portion 316 of the modified secondlayer 331 is not completely removed. The second portion 318 of themodified second layer 331 is at least partially removed, and themodified second layer is at least partially removed from the secondplurality of trenches 112.

The etching process can include a wet etch and/or a dry etch. The wetetch includes exposing the workpiece 300 to an etching chemical, whichcan include DHF, KOH, sulfuric peroxide mix (SPM), phosphoric acid, orany combination of the above. The dry etch includes exposing theworkpiece 300 to an etching chemical, which can include fluorine-basedchemicals, chlorine-based chemicals, oxygen-based chemicals, or anycombination of the above. The etch can be performed at temperatures fromabout 23° C. to about 200° C.

The etching chemistry is based on the composition of the modified secondlayer 331 to be removed. For example, DHF or hydrofluorocarbons (HFC)can be used to remove the modified second layer 331 including SiO,phosphoric acid (H₃PO₄) can be used to remove a modified second layerincluding SiN, and sulfuric peroxide mix (SPM) or oxygen plasma can beused to remove a modified second layer including carbon.

At operation 360 of the method 350, the mask 120 is removed from theworkpiece 300, as depicted in FIG. 5F. The mask 120 is removed similarlyto the process described in operation 156 above.

In one or more embodiments, the second layer 330 is deposited using spincoating, the second layer includes diazonaphthoquinone (DNQ) and/ornovolac, the second layer is cured while ultraviolet (UV) light isapplied at a wavelength of about 193 nm to about 500 nm for about 1minute to about 10 minutes, and a dry etch including oxygen plasma isapplied.

In other embodiments, the second layer 330 is deposited using spincoating, the second layer includes polysiloxane or polysilazane, thesecond layer is cured using a baking process at temperatures from about0° C. to about 400° C. while ultraviolet (UV) light is applied at awavelength of about 193 nm to about 500 nm for about 1 minute to about10 minutes, and a dry or wet etch is performed.

In other embodiments, the second layer 330 is deposited using spincoating, the second layer includes an organic planarization layer (OPL)including a polymer including C and H, the second layer is cured using abaking process at temperatures from about 250° C. to about 400° C., anda dry etch including oxygen plasma is applied.

As described above, a second layer is deposited on the first layer,filling both the first plurality of trenches and the second plurality oftrenches. The second layer is exposed to a curing process, convertingthe second layer to a modified second layer. A mask is placed over thefirst portion of the second layer. The workpiece is exposed to anetching process, which removes the second portion of the modified secondlayer. Finally, the mask is removed. The remaining cured compositionfills the first plurality of trenches, but the second plurality oftrenches is empty.

The mask protects the second plurality of trenches from being filledwith a cured second layer, while still allowing the first plurality oftrenches to be filled with the cured second layer. The method asdescribed above works well for films that require curing to be etched.

In one or more embodiments, the process 150 and/or 250 and/or 350 andany operations or portions thereof, can be performed in a CVD chamber,such as a thermal CVD chamber, a PE-CVD chamber, a high-density plasmaCVD chamber, a low pressure CVD chamber, a reduced pressure CVD chamber,or an atmospheric pressure CVD chamber. In other embodiments, theprocess 150 and/or 250 and/or 250 and any operations or portionsthereof, can be performed in a PVD chamber, an ALD chamber, a PE-ALDchamber, an etch chamber (thermal or plasma), an epitaxy chamber, ananneal chamber, or any other processing chamber in which temperaturemonitoring might be useful. Examples of the processing chamber caninclude CVD chambers such as AKT® PECVD chambers, PRODUCER™ chambers,Eterna FCVD® chambers, and PRECISION 5000® chambers, commerciallyavailable from Applied Materials Inc., Santa Clara, Calif.

In other embodiments, the process 150 and/or 250 and/or 350 and anyoperations or portions thereof, the surfaces of the workpiece 200 areexposed to a dry-clean treatment to remove oxides, carbons,particulates, and/or other contaminants. Any suitable dry-cleantreatment process that removes oxides from the substrate withoutsignificantly damaging the workpiece 100, 200, 300 can be used. Suitabledry-clean treatment processes include sputter etch processes,plasma-based oxide etch processes, or combinations thereof. Thedry-clean treatment can include exposing the workpiece 100, 200, 300 toan etchant and to plasma, ions, radicals, or a combination thereof. Theetchant can be or include one or more oxygen, fluorine, chlorine,nitrogen, plasmas thereof, ions thereof, radicals thereof, or anycombination thereof. The dry-clean treatment includes exposing theworkpiece 100, 200, 300 to a fluorine plasma generated from acombination of nitrogen trifluoride (NF₃) and ammonia (NH₃). Othercontemplated etch processes include NF₃/NH₃ inductively coupled plasmaprocesses or NF₃/NH₃ capacitively coupled plasma processes.

In one or more embodiments, the dry-clean treatment is a plasma-basedoxide etch process that is a remote plasma assisted dry etch processwhich involves the simultaneous exposure of a substrate to NF₃ and NH₃plasma by-products. In some examples, the plasma-based oxide etchprocess can include a SICONI® etch process that is commerciallyavailable from Applied Materials, Inc. of Santa Clara, Calif. TheSICONI® etch process can be performed in a SICONI® Preclean chamber,commercially available from Applied Materials, Inc. of Santa Clara,Calif.

In some examples that use remote plasma, excitation of the gas speciesallows plasma-damage-free substrate processing. The remote plasma etchcan be largely conformal and selective towards silicon oxide layers, andthus does not readily etch silicon regardless of whether the silicon isamorphous, crystalline or polycrystalline. The remote plasma processwill generally produce solid by-products which grow on the surface ofthe workpiece 100, 200, 300 as material is removed. The solidby-products can be subsequently removed via sublimation when thetemperature of the workpiece 100, 200, 300 is raised (e.g., to about300° C.). The plasma etch process results in the removal of oxides,particulate, and other contaminants from the surface of the workpiece100, 200, 300.

In some examples, the dry-clean treatment process can be performed tothe workpiece 100, 200, 300 in a processing chamber using or fluidlycouple to a remote plasma source (RPS). For example, the processingchamber can be an AKTIV Pre-Clean® chamber, commercially available fromApplied Materials, Inc. of Santa Clara, Calif. In other examples, thedry-clean treatment process can be performed in an etch chamber using aninductively coupled plasma (ICP) source. For example, the etch chambercan be a Centura® Advantedge® Mesa® Etch chamber, commercially availablefrom Applied Materials, Inc. of Santa Clara, Calif. Alternatively, thecleaning process can be performed in an etch chamber employing aradical-based chemistry. The workpiece 100, 200, 300 is exposed to theetchant during the dry-clean treatment to remove the contaminants for aperiod of about 20 minutes or less, for example, about 10 minutes.

In one or more examples, the chemical properties of deposited film areutilized to produce selectivity and pattern, instead of relying onphotoresist/hard mask. In one or more embodiments, the mask can be aseparate, removable, and/or reusable part transferring to the processingchamber with the workpiece and/or substrate, or incorporated as ahardware component in tool and/or processing chamber. In otherembodiments, a binary mask can be a contact mask which is placed on theworkpiece and transferred to the processing chamber together orincorporated to the processing chamber design.

Embodiments of the present disclosure further relate to any one or moreof the following paragraphs 1-33:

1. A method for processing a workpiece, comprising: applying a mask on afirst layer disposed on a substrate, wherein the mask covers a firstportion of the first layer and leaves exposed a second portion of thefirst layer; depositing a second layer on the second portion of thefirst layer; and removing the mask from the first portion of the firstlayer, wherein the first portion of the first layer is exposed and thesecond portion of the first layer contains the second layer depositedthereon.

2. A method for processing a workpiece, comprising: depositing a secondlayer comprising an uncured composition on a first layer disposed on asubstrate; applying a mask on the second layer, wherein the mask coversa first portion of the second layer and leaves exposed a second portionof the second layer; exposing the mask and the second portion of thesecond layer to a curing process, wherein the mask shields the firstportion of the second layer from the curing process while the secondportion of the second layer is at least partially cured during thecuring process, and wherein subsequent to the curing process, the firstportion of the second layer comprises the uncured composition and thesecond portion of the second layer comprises a cured composition formedfrom the uncured composition; and removing the mask and the firstportion of the second layer comprising the uncured composition.

3. A method for processing a workpiece, comprising: depositing a secondlayer comprising an uncured composition on a first layer disposed on asubstrate, wherein the first layer comprises one or more structuresformed therein, and wherein the one or more structures comprise verticalfins, slanted fins, or pillars; applying a mask on the second layer,wherein the mask covers a first portion of the second layer and leavesexposed a second portion of the second layer; exposing the mask and thesecond portion of the second layer to a curing process, wherein the maskshields the first portion of the second layer from the curing processwhile the second portion of the second layer is at least partially curedduring the curing process, and wherein subsequent to the curing process,the first portion of the second layer comprises the uncured compositionand the second portion of the second layer comprises a cured compositionformed from the uncured composition; and removing the mask and the firstportion of the second layer comprising the uncured composition.

4. A method for processing a workpiece, comprising: applying a mask on afirst layer disposed on a substrate, wherein the mask covers a firstportion of the first layer and leaves exposed a second portion of thefirst layer; depositing a second layer on the second portion of thefirst layer; removing the mask from the first portion of the firstlayer, wherein the first portion of the first layer is exposed and thesecond portion of the first layer contains the second layer depositedthereon; and exposing the second layer to a curing process.

5. A method for processing a workpiece, comprising: depositing a secondlayer comprising an uncured composition on a first layer disposed on asubstrate; applying a mask on the second layer, wherein the mask coversa first portion of the second layer and leaves exposed a second portionof the second layer; exposing the mask and the second portion of thesecond layer to a curing process, wherein the mask shields the firstportion of the second layer from the curing process while the secondportion of the second layer is at least partially cured during thecuring process, and wherein subsequent to the curing process, the firstportion of the second layer comprises the uncured composition and thesecond portion of the second layer comprises a cured composition formedfrom the uncured composition; and removing the mask and the firstportion of the second layer comprising the uncured composition.

6. A method for processing a workpiece, comprising: depositing a secondlayer comprising an uncured composition on a first layer disposed on asubstrate; applying a mask on the second layer, wherein the mask coversa first portion of the second layer and leaves exposed a second portionof the second layer; exposing the mask and the second portion of thesecond layer to an etching process, wherein the mask shields the firstportion of the second layer from the etching process while the secondportion of the second layer is at least partially etched during theetching process; and removing the mask.

7. The method according to any one of paragraphs 1-6, wherein the secondportion of the first layer comprises a second plurality of trenches, andat least one of the second plurality of trenches makes an angle of about15° to about 75° with respect to a surface of the first layer.

8. The method according to any one of paragraphs 1-7, wherein the firstportion of the first layer comprises a first plurality of trenches, andat least one of the first plurality of trenches makes an angle of about15° to about 75° with respect to a surface of the first layer.

9. The method according to any one of paragraphs 1-8, wherein the curingprocess is selected from a group consisting of a thermal curing process,an ultraviolet curing process, a plasma-assisted treatment process, anion beam treatment process, an e-beam treatment, a baking treatment, andany combination thereof.

10. The method according to any one of paragraphs 1-9, wherein thesecond layer is exposed to ozone during the curing process.

11. The method according to any one of paragraphs 1-10, furthercomprising removing residual material from the first portion of thefirst layer during an etching process subsequent to removing the mask.

12. The method according to any one of paragraphs 1-11, wherein the maskand the first portion of the second layer are removed during the sameprocess.

13. The method according to any one of paragraphs 1-12, wherein thefirst portion of the second layer is removed by an etching process.

14. The method according to any one of paragraphs 1-13, furthercomprising curing the second layer with a curing process before theapplying the mask on the second layer.

15. The method according to any one of paragraphs 1-14, subsequent toremoving the mask, further comprising removing residual material fromthe first portion of the first layer during an etching process.

16. The method according to any one of paragraphs 1-15, wherein theetching process is a wet etch process and includes exposing the residualmaterial to a solution comprising hydrofluoric acid, phosphoric acid, ahydroxide, or salts thereof.

17. The method according to any one of paragraphs 1-16, wherein theetching process is a dry etch process and includes exposing the residualmaterial to plasma comprising fluorine, chlorine, compounds thereof,ions thereof, or any combination thereof.

18. The method according to any one of paragraphs 1-17, furthercomprising curing the second layer during a thermal curing process, anultraviolet curing process, a plasma-assisted treatment process, an ionbeam treatment process, an e-beam treatment, or any combination thereof.

19. The method according to any one of paragraphs 1-18, wherein thesecond layer is exposed to ozone during the curing process.

20. The method according to any one of paragraphs 1-19, wherein thefirst layer comprises one or more structures formed therein.

21. The method according to any one of paragraphs 1-20, wherein the oneor more structures comprise vertical fins, slanted fins, or pillars.

22. The method according to any one of paragraphs 1-21, wherein the oneor more structures are in the second portion of the first layer.

23. The method according to any one of paragraphs 1-22, wherein thesecond layer is deposited within spaces between the one or morestructures.

24. The method according to any one of paragraphs 1-23, wherein thesecond layer is deposited by chemical vapor deposition, atomic layerdeposition, physical vapor deposition, ion beam deposition,spin-coating, or any combination thereof.

25. The method according to any one of paragraphs 1-24, wherein thesecond layer comprises silicon oxide, silicon oxynitride, siliconnitride, silicon oxycarbide, amorphous silicon, polysilicon, alloysthereof, dopant derivatives thereof, or any combination thereof.

26. The method according to any one of paragraphs 1-25, wherein the maskcomprises a contact mask, a proximity mask, a projection mask, or dicingtape.

27. The method according to any one of paragraphs 1-26, wherein the maskhas a thickness of about 10 μm to less than 1 mm.

28. The method according to any one of paragraphs 1-27, wherein the maskhas a thickness of about 50 μm to about 900 μm.

29. The method according to any one of paragraphs 1-28, wherein the maskhas a thickness of about 100 μm to about 500 μm.

30. The method according to any one of paragraphs 1-29, wherein thefirst layer is a surface of the substrate.

31. The method according to any one of paragraphs 1-30, wherein the maskis removed before removing and the first portion of the second layer.

32. The method according to any one of paragraphs 1-31, wherein the maskand the first portion of the second layer are removed during the sameprocess.

33. The method according to any one of paragraphs 1-32, wherein thefirst portion of the second layer is removed by an etching process.

While the foregoing is directed to embodiments of the disclosure, otherand further embodiments may be devised without departing from the basicscope thereof, and the scope thereof is determined by the claims thatfollow. All documents described herein are incorporated by referenceherein, including any priority documents and/or testing procedures tothe extent they are not inconsistent with this text. As is apparent fromthe foregoing general description and the specific embodiments, whileforms of the present disclosure have been illustrated and described,various modifications can be made without departing from the spirit andscope of the present disclosure. Accordingly, it is not intended thatthe present disclosure be limited thereby. Likewise, the term“comprising” is considered synonymous with the term “including” forpurposes of United States law. Likewise whenever a composition, anelement or a group of elements is preceded with the transitional phrase“comprising”, it is understood that we also contemplate the samecomposition or group of elements with transitional phrases “consistingessentially of,” “consisting of”, “selected from the group of consistingof,” or “is” preceding the recitation of the composition, element, orelements and vice versa.

Certain embodiments and features have been described using a set ofnumerical upper limits and a set of numerical lower limits. It should beappreciated that ranges including the combination of any two values,e.g., the combination of any lower value with any upper value, thecombination of any two lower values, and/or the combination of any twoupper values are contemplated unless otherwise indicated. Certain lowerlimits, upper limits and ranges appear in one or more claims below.

What is claimed is:
 1. A method for processing a workpiece, comprising:depositing a second layer comprising an uncured composition directly ona first layer disposed on a substrate; applying a mask directly on thesecond layer, wherein the mask covers a first portion of the secondlayer and leaves exposed a second portion of the second layer, wherein afirst portion of the first layer is disposed below the first portion ofthe second layer and a second portion of the first layer is disposedbelow the second portion of the second layer, and wherein the firstportion of the first layer comprises a first plurality of trenches;exposing the mask and the second portion of the second layer to a curingprocess, wherein the mask shields the first portion of the second layerfrom the curing process while the second portion of the second layer isat least partially cured during the curing process, and whereinsubsequent to the curing process, the first portion of the second layercomprises the uncured composition and the second portion of the secondlayer comprises a cured composition formed from the uncured composition;and removing the mask and the first portion of the second layercomprising the uncured composition.
 2. The method of claim 1, whereinthe at least one of the first plurality of trenches makes an angle ofabout 15° to about 75° with respect to a surface of the first layer. 3.The method of claim 1, wherein the second portion of the first layercomprises a second plurality of trenches, and at least one of the secondplurality of trenches makes an angle of about 15° to about 75° withrespect to a surface of the first layer.
 4. The method of claim 3,wherein the first portion of the first layer comprises a first pluralityof trenches, and at least one of the first plurality of trenches makesan angle of about 15° to about 75° with respect to a surface of thefirst layer.
 5. The method of claim 1, wherein the mask and the firstportion of the second layer are removed during the same process.
 6. Themethod of claim 1, wherein the first portion of the second layer isremoved by an etching process.
 7. The method of claim 1, wherein thecuring process is selected from a group consisting of a thermal curingprocess, an ultraviolet curing process, a plasma-assisted treatmentprocess, an ion beam treatment process, an e-beam treatment, a bakingtreatment, and any combination thereof.
 8. A method for processing aworkpiece, comprising: depositing a second layer comprising an uncuredcomposition directly on a first layer disposed on a substrate, wherein afirst portion of the first layer comprises a first plurality oftrenches; applying a mask directly on the second layer, wherein the maskcovers a first portion of the second layer and leaves exposed a secondportion of the second layer; exposing the mask and the second portion ofthe second layer to a curing process, wherein the mask shields the firstportion of the second layer from the curing process while the secondportion of the second layer is at least partially cured during thecuring process, and wherein subsequent to the curing process, the firstportion of the second layer comprises the uncured composition and thesecond portion of the second layer comprises a cured composition formedfrom the uncured composition; and removing the mask and the firstportion of the second layer comprising the uncured composition duringthe same process.
 9. The method of claim 8, wherein the first portion ofthe first layer is disposed below the first portion of the second layerand a second portion of the first layer is disposed below the secondportion of the second layer, and wherein the first portion of the firstlayer comprises a first plurality of trenches, and at least one of thefirst plurality of trenches makes an angle of about 15° to about 75°with respect to a surface of the first layer.
 10. The method of claim 8,wherein the first portion of the first layer is disposed below the firstportion of the second layer and a second portion of the first layer isdisposed below the second portion of the second layer, and wherein thesecond portion of the first layer comprises a second plurality oftrenches, and at least one of the second plurality of trenches makes anangle of about 15° to about 75° with respect to a surface of the firstlayer.
 11. The method of claim 10, wherein the first portion of thefirst layer comprises a first plurality of trenches, and at least one ofthe first plurality of trenches makes an angle of about 15° to about 75°with respect to a surface of the first layer.
 12. The method of claim 8,wherein the first portion of the second layer is removed by an etchingprocess.
 13. The method of claim 8, wherein the curing process isselected from a group consisting of a thermal curing process, aplasma-assisted treatment process, an ion beam treatment process, ane-beam treatment, a baking treatment, and any combination thereof.
 14. Amethod for processing a workpiece, comprising: depositing a second layercomprising an uncured composition directly on a first layer disposed ona substrate, wherein a first portion of the first layer comprises afirst plurality of trenches; applying a mask directly on the secondlayer, wherein the mask covers a first portion of the second layer andleaves exposed a second portion of the second layer; exposing the maskand the second portion of the second layer to a curing process, whereinthe mask shields the first portion of the second layer from the curingprocess while the second portion of the second layer is at leastpartially cured during the curing process, and wherein subsequent to thecuring process, the first portion of the second layer comprises theuncured composition and the second portion of the second layer comprisesa cured composition formed from the uncured composition; and removingthe mask and the first portion of the second layer comprising theuncured composition, wherein the first portion of the second layer isremoved by an etching process.
 15. The method of claim 14, wherein thefirst portion of the first layer is disposed below the first portion ofthe second layer and a second portion of the first layer is disposedbelow the second portion of the second layer, and wherein the firstportion of the first layer comprises a first plurality of trenches, andat least one of the first plurality of trenches makes an angle of about15° to about 75° with respect to a surface of the first layer.
 16. Themethod of claim 14, wherein the first portion of the first layer isdisposed below the first portion of the second layer and a secondportion of the first layer is disposed below the second portion of thesecond layer, and wherein the second portion of the first layercomprises a second plurality of trenches, and at least one of the secondplurality of trenches makes an angle of about 15° to about 75° withrespect to a surface of the first layer.
 17. The method of claim 16,wherein the first portion of the first layer comprises a first pluralityof trenches, and at least one of the first plurality of trenches makesan angle of about 15° to about 75° with respect to a surface of thefirst layer.
 18. The method of claim 14, wherein the mask and the firstportion of the second layer are removed during the same process.
 19. Themethod of claim 14, wherein the curing process is selected from a groupconsisting of a thermal curing process, a plasma-assisted treatmentprocess, an ion beam treatment process, an e-beam treatment, a bakingtreatment, and any combination thereof.